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Chemistry of Particles and Selected Trace Gases at Whistler, BC A.M. Macdonald, K.G. Anlauf and W.R. Leaitch. Chemistry of Particles and Selected Trace Gases at Whistler, BC. Objectives Establish a baseline of particle and trace gas measurements at a lower free-tropospheric site.
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Chemistry of Particles and Selected Trace Gases at Whistler, BCA.M. Macdonald, K.G. Anlauf and W.R. Leaitch
Chemistry of Particles and Selected Trace Gases at Whistler, BC • Objectives • Establish a baseline of particle and trace gas measurements at a lower free-tropospheric site. • Examine incidences of trans-Pacific pollution transport from Asia into western Canada. • 2004/2005 Objectives/Deliverables • Measure sulphate and other inorganic particle chemistry in the free troposphere for a three-year period (Completion of 2003 data set - May 04) • Document frequency and duration of incidences of trans-Pacific transported pollution to the West Coast of Canada (Selection of case studies from summer 2003 - Oct 04) • Provide background ozone climatology at a free-tropospheric site for a three-year period, including springtime maxima associated with photochemistry or troposphere-stratosphere folding events. (Completion of 2003 data set for O3 and CO May 04) • Evaluation of site as a long-term sampling location (Mar 05)
The site is located at Whistler Peak (elevation 2182 m) and operates year-round.
Lift operator’s hut – Sep 2004 Environment Canada samplers
Mar 2002 April 2002 May 2002 June 2002 July 2002 Aug 2002 Sep 2002 Oct 2002 Nov 2002 Dec 2002 Jan 2003 Feb 2003 Mar 2003 April 2003 May 2003 June 2003 July 2003 Aug 2003 Sep 2003 Oct 2003 Nov 2003 Dec 2003 Jan 2004 Feb 2004 Mar 2004 April 2004 May 2004 June 2004 July 2004 Aug 2004 Sep 2004 Instrumentation at Whistler Site March 2002 to October 2004 Ozone CO Filter Packs Particle Distributions PCASP1, DMA2 Dust Monitor Site Visits POPs (PBDEs, PCBs) 1 2 2 2 T, RH, P Ozone and CO calibrations Measurement Periods
Updated logger to 23X • Updated communications software • Files regularly posted to internal web site
Results: Gas phase measurementsData set: Ozone and CO, March 2002 to present Status: QA/QC complete up to March 2004 2003 summer average CO 20% higher than 2002 average
2003: 22.5 Mha 2002: 11.7 Mha 2004: 5.6 Mha From: Jaffe et al., GRL 2004
Results: Particle measurements • Chemistry from Filter packs Status: Flow corrected- Feb 2004 Samples analyzed –June 7, 2004 • Physical characterization from (1) Grimm OPC (300 nm – 30 um) (> 80% data coverage in 2003/2004) (2) DMA (10 nm to 400 nm) • Dec 2003 to May 2004 (> 40% data coverage in 2003/2004)
Particle sulphate at Whistler Peak, < 2.5 um (24 or 48 hour filter packs) April 2002 to February 2004
Soluble inorganics on teflon filters – April 2002 to June 2003 Median sulphate is 0.09 g m-3 with 95 % of the samples less than 0.56 g m-3. The major cation is NH4+ with 95% of the samples less than 0.25 g m-3. Very little mass is found in Ca2+ and Mg2+ with this 2.5 m cut off.
The mean distribution shows two modes, one from approximately 20 to 50 nm and a second in the accumulation mode at about 150 to 200 nm. • initial examination of 2004 data shows similar distributions
particle mass calculated as a sum of analyzed soluble organic ions and mass estimated from the DMA for Feb – Apr 2003. Strong covariance is seen but total mass is underestimated by the soluble inorganic ions.
soluble inorganics account for 5-20% of total mass in these samples Feb to April 2003 • VanCuren (2003) found major fine particle fractions at Crater Lake and Mount Lassen to be ~ 30% mineral, 28% organic, 4% EC, 10% sulphate, <5% nitrate, <1% sea salt
Need to separate influence from local/regional biomass burning
Lonesome Lake Fire, July 28, 2004 MODIS Image Source: Earth Observatory Other tools available: Trajectories, TOMS Aerosol Index
Deliverables 2003/2004: • 2004/2005 Objectives/Deliverables • Measure sulphate and other inorganic particle chemistry in the free troposphere for a three-year period (Completion of 2003 data set - May 04) • Document frequency and duration of incidences of trans-Pacific transported pollution to the West Coast of Canada (Selection of case studies from summer 2003 - Oct 04) March 05 • Provide background ozone climatology at a free-tropospheric site for a three-year period, including springtime maxima associated with photochemistry or troposphere-stratosphere folding events. (Completion of 2003 data set for O3 and CO May 04) • Evaluation of site as a long-term sampling location (Mar 05) • Next Steps: • Installation of temperature sensors at various altitudes. • Continue sampling, increase particle physical measurements • Continue data QA/QC • Installation of NOx instrument • Look for transport scenarios • Collaboration for modeling, vertical profile data • AMS on site for spring 2005 period
Acknowledgements Data analysis - Art Tham Web site – Gary Chung, Kathy Hayden Site visits – Dave Halpin, Maurice Watt, Kathy Hayden, John Deary Sample analyses – CAPMoN Site operators - Juniper Buller, Anton Horvath